CN1133239A - Imagery equipment - Google Patents
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- CN1133239A CN1133239A CN95120128A CN95120128A CN1133239A CN 1133239 A CN1133239 A CN 1133239A CN 95120128 A CN95120128 A CN 95120128A CN 95120128 A CN95120128 A CN 95120128A CN 1133239 A CN1133239 A CN 1133239A
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- 238000003384 imaging method Methods 0.000 claims abstract description 23
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- 229920002799 BoPET Polymers 0.000 description 1
- 239000005041 Mylar™ Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/04—Apparatus for electrographic processes using a charge pattern for exposing, i.e. imagewise exposure by optically projecting the original image on a photoconductive recording material
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/435—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of radiation to a printing material or impression-transfer material
- B41J2/47—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of radiation to a printing material or impression-transfer material using the combination of scanning and modulation of light
- B41J2/471—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of radiation to a printing material or impression-transfer material using the combination of scanning and modulation of light using dot sequential main scanning by means of a light deflector, e.g. a rotating polygonal mirror
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K15/00—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers
- G06K15/02—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers
- G06K15/12—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by photographic printing, e.g. by laser printers
- G06K15/1204—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by photographic printing, e.g. by laser printers involving the fast moving of an optical beam in the main scanning direction
- G06K15/1223—Resolution control, enlarging or reducing, edge or detail enhancement
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
- H04N1/40—Picture signal circuits
- H04N1/40025—Circuits exciting or modulating particular heads for reproducing continuous tone value scales
- H04N1/40037—Circuits exciting or modulating particular heads for reproducing continuous tone value scales the reproducing element being a laser
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Optics & Photonics (AREA)
- General Physics & Mathematics (AREA)
- General Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Exposure Or Original Feeding In Electrophotography (AREA)
- Laser Beam Printer (AREA)
- Facsimile Scanning Arrangements (AREA)
- Mechanical Optical Scanning Systems (AREA)
Abstract
本发明提供了一种成像设备，该成像设备包括：一光敏件；扫描装置，它包括用来发射出扫描光敏件的激光光束的光发射器件；和用来控制光发射器件照度的控制装置。其特征在于：当光敏件上激光光束的移动速度为V，象素一侧边的长度为L，光发射器件对每一象素的最大光发射时间为t时，控制装置按下述关系：t＜L/V来对光发射器件进行控制。
The present invention provides an imaging device comprising: a photosensitive member; a scanning device including a light emitting device for emitting a laser beam for scanning the photosensitive member; and a control device for controlling the illuminance of the light emitting device. It is characterized in that: when the moving speed of the laser beam on the photosensitive member is V, the length of one side of the pixel is L, and the maximum light emitting time of the light-emitting device for each pixel is t, the control device follows the following relationship: t<L/V to control the light-emitting device.
Description
The present invention relates to an imaging device, such as: a duplicator, a printer and similar device especially relate to and a kind ofly utilize laser beam that photosensitive part is scanned and form the imaging device of image.
In imaging device, we know that photoelectricity photography laser printer is a kind of high-speed and low-noise printer.This type of laser printer is normally finished two value records, formed image, such as a symbol, and figure or similar image form by utilizing laser beam and shining on photosensitive part or do not shine.In a word, because symbol, figure or similar record images need not semi-tone, so the class printer arrangement is simpler.
Recently, the someone has proposed a kind of semi-tone pixel formation method, it is characterized in that: need not to reduce packing density and can obtain high-resolution.In the method, can form the image of semi-tone by the pulse width (PWM) of regulating laser beam according to a picture signal.According to this type of PWM system, can form the image of high-resolution and high gradient.Therefore, this type systematic can be used as the color-image forming apparatus that requirement has high-resolution and high gradient.According to this type of PWM system, by utilizing light beam each pixel is shone, just may make formed picture point have regional chromatograph, thereby need not to reduce PEL density (packing density) and can obtain semi-tone.
Thereby even if, still require to improve resolution ratio utilizing laser beam scanning photosensitive part to form in the imaging device of image.Can consider resolution ratio to be risen by the spot diameter that reduces laser beam.But for the spot diameter that makes laser beam is reduced, the enlargement ratio of condenser lens just needs to improve, so imaging device will become heavy and expensive.Moreover, owing to depth of focus reduces, therefore just unstable to the focusing of photosensitive part.
The present invention helps to eliminate above-mentioned common deficiency, the objective of the invention is to, and a kind of imaging device that obtains high-resolution picture is provided.
Another object of the present invention provides a kind of imaging device, and this imaging device is characterised in that: the spot diameter of laser beam can reduce.
Another object of the present invention is to provide a kind of imaging device, this imaging device comprises: a photosensitive part; The one scan device, it comprises the light emitting devices of launching the laser beam that is used for scanning photosensitive part; With a control device that is used for controlling light emitting devices illumination.Wherein, the translational speed of laser beam is V on photosensitive part, and the length of pixel one side is L, and when being t launch time for the maximum light of each pixel light emitting devices, control device comes light emitting devices is regulated and control by following relation: t＜L/V.
Other purpose of the present invention will be set forth in the detailed description relevant of the present invention hereinafter.
Fig. 1 is the vertical profile schematic diagram by the imaging device of the present invention's one most preferred embodiment;
Fig. 2 is the schematic diagram by laser scanning part in the imaging device of most preferred embodiment;
Fig. 3 A shows performance by photosensitive part in the imaging device of most preferred embodiment to 3C, and wherein Fig. 3 A shows light sensitive characteristic, and Fig. 3 B shows the hot spot distribution character, and Fig. 3 C shows latent image and distributes;
Fig. 4 A is the schematic diagram that static exposure distributes, and Fig. 4 B is the schematic diagram that scan exposure distributes;
Fig. 5 A and 5B are the schematic diagrames with respect to exposure distribution under the on/off characteristic curve;
Fig. 6 A is the schematic diagram of exposure distribution when light changes launch time to 6C:
Fig. 7 A is the schematic diagram of exposure distribution when light changes launch time to 7C;
Fig. 8 is the block diagram of laser scanning part in the imaging device;
Fig. 9 is the sequential chart of laser scanning component in the imaging device;
Figure 10 A is the schematic diagram of exposure distribution when light changes launch time to 10C;
Figure 11 A is the schematic diagram of exposure distribution when light changes launch time to 11C; With
Figure 12 is used for illustrating the photosensitive part expanded view that each pixel maximum scan was adopted during the time.
Explain the present invention and specific embodiment thereof now with reference to accompanying drawing.
Fig. 1 expresses the imaging device according to a most preferred embodiment of the present invention: an original paper G faces down with the imaging surface that will duplicate and is placed in the original paper support 10.Press copy button then and begin a duplicating circulation.
By parts 9 irradiations and the scanning original paper that utilize one to comprise original paper illuminating lamp, proximity focused set of lenses and ccd sensor, the light that reflects from original paper is focused on the ccd sensor by the proximity focused set of lenses.Ccd sensor comprises a light receiving part, a hop and an output.At light receiving part, optical signal is converted into the signal of telecommunication; At hop, the signal of telecommunication and clock pulses are transferred to output synchronously continuously; At output, current signal is converted into voltage signal, thereby an exportable low-impedance signal that has through amplifying.
Like this, utilize common image processing method that analog signal conversion has been become data signal, data signal outputs to a printer section.In printer section, by forming an electrostatic latent image by following mode response image signal.
A photosensitive drums (photosensitive part) 1 is rotated around rotating shaft with predetermined circumferential speed, and photosensitive drums electricity charging device 3 fills equably with positive charge or negative electrical charge simultaneously.Then, by the uniform charging surface of the laser beam flying photosensitive drums of picture intelligence modulation, the surface of photosensitive drums 1 just formed one with original paper on visual corresponding electrostatic latent image.
Fig. 2 is the schematic illustrations that an expression utilizes laser scanning part (scanning means) 100 of laser beam flying photosensitive drums.
When photosensitive drums is scanned by laser scanning part 100, at first, a Solid State Laser element 102 is subjected to shine in response to the light emission signal generator 101 of picture intelligence, the laser beam that sends from laser scanning part 100 converts collimated light beam to by parallel light tube lens combination 103, and then be deflected along the rotation polygon prism 104 of direction shown in arrow b rotation through one, the laser beam of deflection is by f θ lens 105a by the polygon prism effect, 105b, 105c is focused into a point on the surface (surface that will be scanned) of the face 106 of photosensitive drums 1, like this, be scanned scanning of image distribution of formation on the face 106 by a laser scanning, for each laser scanning, lick a predetermined amount by on the direction vertical (secondary scanning direction), being scanned surface 106, be scanned the scanning distribution that has just formed on the surface 106 corresponding to picture intelligence with the scanning direction.
In this way thereby the electrostatic latent image that forms on photosensitive drums 1 forms a width of cloth subsequently by transmitting the color image that charging device 7 quiet batteries reach material for transfer by developing device 4 developings.After this, material for transfer is by separation of charged device 8 and photosensitive drums electrostatic separation, and the material for transfer after the separation is admitted to color applicator 6, in device 6 places color image by photographic fixing on material for transfer.Then, material for transfer is delivered to outside the equipment as an image output copy.
In addition, after color image is reached material for transfer, stay be cleaned device 5 of photosensitive drums 1 lip-deep remaining color and remove and prepare for next visual imaging.
In illustrated embodiment, photosensitive drums 1 has light sensitive characteristic as shown in Figure 3A.As can be seen from Figure 3A, in little light quantity scope, the charged electric potential on the photosensitive drums 1 does not reduce (the electromotive force attenuation is very little) basically, and when having surpassed a predetermined light quantity threshold value, thereby light sensitive characteristic greatly strengthens and increased the electromotive force attenuation.Photosensitive drums 1 is that the material of the granules of pigments of 0.01-0.5 μ m is formed by being studded with diameter in the high impedance adhesive.For example, fine and closely woven α-copper titanium cyanine particulate dispersion is pressed in the mixture of resin at mylar and honey.
When on the laser facula with Gaussian distribution characteristic shown in Fig. 3 B is possessing the photosensitive drums 1 of above-mentioned light sensitive characteristic, exposing, in little light quantity scope, because sensitivity is little, so made it possible to form the latent image point littler by the latent image characteristic curve shown in cutting as the secondary lobe of Gaussian distribution among Fig. 3 C, thereby obtained high-resolution than laser spot.
Yet the inventor finds that because laser beam moves, therefore actual spot diameter is greater than the spot diameter of estimating on main scanning direction.
Fig. 4 A expresses the distribution shape of its hot spot when laser beam does not scan (inactive state).Yet because in fact laser beam move along direction (main scanning direction) shown in arrow among Fig. 4 B, when with corresponding to the time emission laser beam of a pixel time, hot spot has been enlarged significantly.When such scanning light spot distributes when having photosensitive drums 1 combination of light sensitive characteristic as shown in Fig. 3 A, the latent image of acquisition is put its diameter will be greater than the spot diameter in static hot spot distributes, thereby has hindered the acquisition high-resolution.
With because the exposure distribution that causes of scanning light spot enlarges another relevant problem is: when noting as shown in Fig. 5 A one and can break characteristic curve (each pixel), the secondary lobe of scanning light spot exposure distribution is overlapping can not be ignored.Thereby as shown in Fig. 5 B, the accumulation light quantity of pixel has increased under " breaking " state.
In illustrated embodiment, especially as a kind of binary feature, when this binary feature has the threshold value relevant with the photosensitive drums light sensitive characteristic, if the accumulation light quantity of pixel has surpassed the threshold value relevant with the photosensitive drums light sensitive characteristic when " breaking " state, just can't obtain to have high-resolution image point characteristic curve, although this problem can be resolved by as mentioned above spot diameter being accomplished little method to pixel size, produced the problem relevant with precision with the cost of equipment.Therefore, along with the increase of resolution ratio, constitute a desirable equipment and will become difficult more.
The present invention can improve resolution ratio by a method that makes laser facula have the diameter of pixel size.Key point of the present invention is to suppress because the actual hot spot that laser facula scanning (moving) causes enlarges and the expansion of exposure distribution secondary lobe.
For accomplishing this point, light rate launch time of the laser light beam source of each pixel is less than the driving time cycle of a pixel.That is to say that the translational speed of laser beam is V on photosensitive part, the length of pixel one side is that be t maximum light launch time of the laser beam emission part of L and corresponding each pixel, then controls light emission part and makes it satisfy relation: t＜L/V.
More detailed explanation as shown in Figure 12, when the image taking speed relevant with recording materials (peripheral speed of photosensitive drums) is 160mm/sec (mm/second), packing density is 400dpi (each pixel size is 63.5 μ n * 63.5 μ m), the ratio of effective scanning length and total sweep length is 51.2% and is 300mm corresponding to the photosensitive drums length of effective scanning area that be calculated as follows the sweep time of each pixel:
t1＝(63.5μm÷160mm/sec)×0.512/4725＝43nsec
Correspondingly, in illustrated embodiment, the maximum scan time of each pixel is chosen to be t＜43nsec.
On the other hand, can write out following expression formula.Consider the on/off characteristic curve of each pixel, when light rate launch time (light emitting time rate) of laser light beam source when T1 is 1, relation below the light rate launch time T1 of the laser light beam source relevant with the driving time of a pixel satisfies:
T1＜(3L－S)/L
Wherein, L is a pixel size, and S is the l/e of LASER SPECKLE diameter
2(the l/e of diameter
2≌ 14% is relevant with the maximum of Gaussian distribution; Be used for representing " spot diameter " hereinafter) and 0＜T1＜1.
When laser facula during much larger than pixel size, by shortening driving pulse fully with respect to a pixel driving time, the expansion of actual hot spot can be eliminated.
Using laser beam according to illustrated embodiment and having in the high-resolution two-value printer, can be that the desired performance of log resolution writes down the on/off characteristic curve by forming two value records.Correspondingly, when a characteristic curve such as on/off/on/off was exported, the accumulation light quantity of pixel was no more than because the photosensitive drums luminous sensitivity threshold that the expansion of laser facula secondary lobe causes is very important under disconnected state.
From various experiments, can find, have in application under the situation of photosensitive drums 1 of two-value light sensitive characteristic of illustrated embodiment, when the laser emission time of each pixel shortened as mentioned above, as long as spot diameter is 2 times of pixel size or slightly smaller, two value records just effectively.For example, when resolution ratio is 600dpi, as long as be about 80～85 μ m or littler corresponding to the spot diameter of the about 42 μ m of pixel size, the on/off characteristic curve just can be in follow-up developing process developing.
If yet spot diameter surpasses above-mentioned value, the exposure distribution between the pixel just can not be left in the basket, and can also find, even if used the photosensitive drums of illustrated embodiment, it also is difficult forming stable on/off characteristic curve.In addition, from relevant resolution ratio is the similar experiment of 1200dpi, can find as long as be about 40 μ m or when slightly smaller corresponding to the spot diameter of the about 21 μ m of pixel size, just can be in follow-up developing process this on/off characteristic curve of developing.
Like this, by shortening laser beam launch time by above-mentioned formula corresponding to pixel driving time, even if used the spot diameter greater than above-mentioned diameter, the hot spot that also can reduce to be caused by scanning enlarges, and has consequently stoped the expansion of latent image.
Fig. 6 A to 6C expresses when the exposure distribution of spot diameter during greater than pixel size 2 times (S=2L).From Fig. 6 A to 6C as can be seen, T1 is made as 0.5 when light rate launch time, and the scanning direction of each pixel can reduce by half, and consequently the latent image that is caused by scanning enlarges half that can reduce to pixel and enlarge.In addition, along with reducing of light rate launch time,, latent image allows to produce two stable value records thereby having higher contrast ratio.When light reduced launch time, the accumulation light quantity of laser beam also reduced, and therefore, in the embodiment shown in Fig. 6 A to 6C, along with the light minimizing of launch time, the electric current that acts on light emission part increases, thereby has suppressed the minimizing of accumulation light quantity.In addition, by reducing the scanning direction, just can use bigger spot diameter.
From above-mentioned formula as can be seen, such as, when time rate is 0.1, can ignore basically by the latent image expansion that scanning causes, consequently adoptable spot diameter can increase to two to three times of normal light spot diameter.
Fig. 7 A to 7C expresses as S=ZL (T1=1), the corresponding exposure distribution that obtains when S=2.5L (T1=0.5) and S=2.9L (T1=0.1).If use big hot spot,, can obtain similar Hurter and Driffield curve by reducing luminous emissivity T1.
This to obtain to have can form 600dpi or the more high-resolution output of high record density be very important.In illustrated embodiment, can use big hot spot and obtain one to have high-resolution cheap printer.
In addition, when luminous emissivity reduces,, must increase the emission measure (for example, when luminous emissivity was 0.5, the laser beam emission measure was increased to original two times) of laser beam according to luminous emissivity because the accumulation light quantity also reduces.
Second embodiment
To explain second embodiment below, it is characterized in that, realize the polychrome record by modulating a laser pulse width on the pixel.
Fig. 8 expresses a circuit block diagram of describing the pulse width modulation circuit example, TTL lock-in circuit that is used to lock 8 digital bit picture signals of label 401 expressions; It is the level translator of High Speed ECL logic level that 402 one of expression are used for the TTL logic level transition; It is the D/A converter of analog signal that 403 one of expression are used for the ECL logic level transition; ECL comparator that is used to produce pwm signal of 404 expressions; It is the level translator of TTL logic level that 405 one of expression are used for the ECL logic level transition; Clock oscillator that is used for transmit clock signal 2f of 406 expressions; 407 one of expression are used to produce the triangular-wave generator with the synchronous desirable triangular signal of clock signal 2f; 408 one of expression are used for clock signal 2f is divided equally to produce 1/2 frequency divider of image clock signal f.
According to this circuit, the frequency of clock signal 2f is the twice of image clock signal f frequency.By the way, run at high speed, used the ECL logic circuit for making circuit.
Explain foregoing circuit now with reference to sequential chart shown in Figure 9, signal a represents clock signal 2f, signal b presentation video clock signal f, and these signals are relevant with picture signal.In addition, in triangular-wave generator 407,, after clock signal 2f is by 1/2 frequency division, produced triangular signal C for the dutycycle that keeps triangular signal is 50%.In addition, triangular signal C be converted into the ECL level (0 to-1V) form triangular signal d.
On the other hand, picture signal is converted into from OOh (in vain) to 256 colourities of FFh (deceiving).Symbol " h " expression 16 system numbers.The ECL level of picture signal C for converting to by picture signal D/A.For example, first pixel has FFh level (black pixel level), and second pixel has 80h level (middle chroma level), and the 3rd pixel has 40h level (middle chroma level), and the 4th pixel has 20h level (middle chroma level).
In first embodiment, can form the on/off characteristic curve of two pixels by two-value, yet in second embodiment, because the break-make of laser generation effect and spot diameter in a pixel form the level in zone with this rate variation, the unstability that the image point that is produced by the influence of the secondary lobe between adjacent image point forms is compared much serious with first embodiment.Figure 10 A to 10C expresses such example.
Figure 10 A to 10C expresses the light quantity that is obtained during greater than 1.5 times (S=1.52) of pixel size when spot diameter.Figure 10 A represents a kind of situation when smooth launch time, rate T2 was 1 (primary condition), and Figure 10 B represents the situation of T2=0.5, and Figure 10 C represents the situation of T2=0.25.
Especially in Figure 10 B,, for each pixel, can produce the minimizing that position deviation causes charged electric potential, thereby cause judder because light quantity is positioned near the threshold value.On the other hand, in Figure 10 C, because light quantity can't surpass threshold value, charged electric potential does not reduce, consequently can't imaging.
Can address the above problem according to high-resolution many-valued printer with illustrated embodiment.Realize that by the pulse width modulation laser emission time even if laser beam moves (scanning) on photosensitive part, the remarkable expansion of spot diameter also can be suppressed in the polychrome degree record imaging device at one.
Embodied a kind of like this device in the illustrated embodiment: when the translational speed of laser beam on photosensitive part is V, the length of pixel one side is L, and be t maximum light launch time of corresponding each pixel laser beam launching condition, then controls light emission part and concern t＜L/V to satisfy.
In addition, corresponding to the driving time of a pixel, the light rate launch time T2 of laser light beam source can be made as satisfy below relation: T2＜(2L-S)/L.
Wherein, L is a pixel size, and S is laser facula 1/e
2Diameter (diameter 1/e
2≌ 14% is corresponding to the maximum of Gaussian distribution; Only refer to " spot diameter " hereinafter), and 0＜T2＜1.
Pulse width modulation is effective in the scope of the light rate launch time T2 that does not surpass lasing light emitter the time.Therefore, when laser facula during,, can eliminate the expansion of actual hot spot by shortening the Laser Driven pulse fully corresponding to a pixel driving time much larger than pixel size.
In pressing the high-resolution many-valued printer of illustrated embodiment, the on/off characteristic curve must come record by forming the desired performance of many-valued record, promptly within a pixel of log resolution.Correspondingly, when the colourity record had also been finished in the middle of realizing in PWM is modulated at a pixel, it was very important enlarging the luminous sensitivity threshold that accumulation light quantity between caused adjacent image point is no more than photosensitive drums by the secondary lobe of laser facula.
From various experiments, can find: have in use under the situation of photosensitive drums 1 of two-value light sensitive characteristic of illustrated embodiment, as long as spot diameter equates with pixel size just can realize many-valued record.For example, can find: when resolution ratio is 600dpi, as long as be about 42 μ m or still less corresponding to the spot diameter of the pixel size of about 42 μ m, well-bedded image just can be in follow-up developing process developing.Yet, if spot diameter surpasses above-mentioned value,, and can find:, also be difficult to form stable level even if used the photosensitive drums of illustrated embodiment just the influence of exposure distribution can not be ignored between pixel.Especially in the middle colourity district with long pulse width time, the actual hot spot that causes owing to scanning enlarges and the expansion of secondary lobe makes accumulation light quantity between adjacent image point surpass the luminous sensitivity threshold of photosensitive drums 1, so can't realize the region gradient record.
In illustrated embodiment, by by above-mentioned formula in very short scope corresponding to pixel driving time utilization pulse width modulation laser beam launch time, even acted on spot diameter greater than above-mentioned diameter, the hot spot expansion that is caused by scanning still can be reduced, and consequently avoids the expansion of latent image.For example, when maximum light rate launch time is made as 0.5, the scanning direction of each pixel can reduce by half, and consequently the latent image that is caused by scanning enlarges half that can reduce to pixel and enlarge.Therefore, along with reducing of light rate launch time, latent image has higher contrast ratio, thereby can realize stable many-valued record.
Such example is shown in Figure 11 A to 11C, and they have represented the light quantity that obtained during greater than 1.5 times (S=1.5L) of pixel size when spot diameter.Figure 11 A represents that light rate launch time T2 is the situation of 0.5 (primary condition), and Figure 11 B represents the situation of T2=0.25, and Figure 11 C represents the situation of T2=0.125.In addition, because scanning distance reduces, can use sizable hot spot.
By above-mentioned formula, for example,, can ignore substantially by the latent image expansion that scanning causes when time rate T2 is 0.1, consequently the spot diameter that is adopted can increase to the twice of normal light spot diameter.
This to obtain to have can form 600dpi or more the high-resolution output of high record density be very important, and in illustrated embodiment, can use big hot spot and obtain having high-resolution cheap printer.
When initial light reduces launch time, because the accumulation light quantity also reduces, must according to light rate launch time increase the laser beam emission measure (for example, when luminous emissivity be 0.5, the laser beam emission measure will be increased to twice), this can understand by the waveform height between comparison diagram 10A and the 11A.
The present invention is not limited to illustrated embodiment, can realize various modification within the scope of the invention.
Claims (3)
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP338006/94 | 1994-12-27 | ||
| JP338006/1994 | 1994-12-27 | ||
| JP6338006A JPH08185021A (en) | 1994-12-27 | 1994-12-27 | Image forming device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1133239A true CN1133239A (en) | 1996-10-16 |
| CN1071201C CN1071201C (en) | 2001-09-19 |
Family
ID=18314068
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN95120128A Expired - Fee Related CN1071201C (en) | 1994-12-27 | 1995-12-27 | Imagery equipment |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US5877799A (en) |
| EP (1) | EP0720346B1 (en) |
| JP (1) | JPH08185021A (en) |
| KR (1) | KR0179189B1 (en) |
| CN (1) | CN1071201C (en) |
| DE (1) | DE69518218T2 (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3596574B2 (en) * | 1996-11-18 | 2004-12-02 | 富士写真フイルム株式会社 | Thermal recording method |
| JP3237704B2 (en) | 1998-11-06 | 2001-12-10 | 日本電気株式会社 | High resolution circuit |
| JP2001296684A (en) * | 2000-04-11 | 2001-10-26 | Mitsubishi Chemicals Corp | Toner and image forming method |
| JP2002040680A (en) * | 2000-05-17 | 2002-02-06 | Mitsubishi Chemicals Corp | Image forming method and image forming apparatus |
| JP2002040681A (en) * | 2000-05-19 | 2002-02-06 | Mitsubishi Chemicals Corp | Image forming method and image forming apparatus |
| JP2002040704A (en) * | 2000-05-19 | 2002-02-06 | Mitsubishi Chemicals Corp | Image forming method and image forming apparatus |
| JP2002049164A (en) * | 2000-05-22 | 2002-02-15 | Mitsubishi Chemicals Corp | Image forming method and image forming apparatus |
| US20040005700A1 (en) * | 2002-05-28 | 2004-01-08 | Surber Mark W. | Poroplasts |
| JP4713351B2 (en) * | 2006-01-27 | 2011-06-29 | 株式会社リコー | Image forming apparatus, image forming method, and program |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2669531B2 (en) * | 1988-04-27 | 1997-10-29 | 富士写真フイルム株式会社 | Light beam recording device |
| US5017944A (en) * | 1989-03-06 | 1991-05-21 | Victor Company Of Japan, Ltd. | Control system for information recording laser beam |
| DE69034055D1 (en) * | 1989-10-02 | 2003-05-08 | Canon Kk | Imaging device and modulation method |
| US5341165A (en) * | 1991-01-16 | 1994-08-23 | Canon Kabushiki Kaisha | Scanning controller for color electrophotographic apparatus |
| JP2965364B2 (en) * | 1991-01-17 | 1999-10-18 | 株式会社リコー | Optical scanning method and optical scanning device |
| US5279277A (en) * | 1992-08-03 | 1994-01-18 | Barker Gordon R | Heat radiating element and drippings shield for gas-fired barbecues |
-
1994
- 1994-12-27 JP JP6338006A patent/JPH08185021A/en active Pending
-
1995
- 1995-12-26 US US08/586,625 patent/US5877799A/en not_active Expired - Lifetime
- 1995-12-27 DE DE69518218T patent/DE69518218T2/en not_active Expired - Lifetime
- 1995-12-27 CN CN95120128A patent/CN1071201C/en not_active Expired - Fee Related
- 1995-12-27 KR KR1019950059694A patent/KR0179189B1/en not_active Expired - Lifetime
- 1995-12-27 EP EP95309447A patent/EP0720346B1/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| EP0720346A2 (en) | 1996-07-03 |
| KR0179189B1 (en) | 1999-04-01 |
| EP0720346B1 (en) | 2000-08-02 |
| EP0720346A3 (en) | 1996-12-04 |
| DE69518218D1 (en) | 2000-09-07 |
| US5877799A (en) | 1999-03-02 |
| CN1071201C (en) | 2001-09-19 |
| KR960024745A (en) | 1996-07-20 |
| DE69518218T2 (en) | 2001-03-29 |
| JPH08185021A (en) | 1996-07-16 |
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